diff --git a/uvicorn/protocols/http/h11_impl.py b/uvicorn/protocols/http/h11_impl.py
index 6a362ff20..e9583d70b 100644
--- a/uvicorn/protocols/http/h11_impl.py
+++ b/uvicorn/protocols/http/h11_impl.py
@@ -113,7 +113,6 @@ def __init__(self, config, server_state, _loop=None):
         self.scope = None
         self.headers = None
         self.cycle = None
-        self.message_event = asyncio.Event()
 
     # Protocol interface
     def connection_made(self, transport):
@@ -146,7 +145,8 @@ def connection_lost(self, exc):
                 # Premature client disconnect
                 pass
 
-        self.message_event.set()
+        if self.cycle is not None:
+            self.cycle.message_event.set()
         if self.flow is not None:
             self.flow.resume_writing()
 
@@ -234,7 +234,7 @@ def handle_events(self):
                     access_logger=self.access_logger,
                     access_log=self.access_log,
                     default_headers=self.default_headers,
-                    message_event=self.message_event,
+                    message_event=asyncio.Event(),
                     on_response=self.on_response_complete,
                 )
                 task = self.loop.create_task(self.cycle.run_asgi(app))
@@ -247,7 +247,7 @@ def handle_events(self):
                 self.cycle.body += event.data
                 if len(self.cycle.body) > HIGH_WATER_LIMIT:
                     self.flow.pause_reading()
-                self.message_event.set()
+                self.cycle.message_event.set()
 
             elif event_type is h11.EndOfMessage:
                 if self.conn.our_state is h11.DONE:
@@ -255,7 +255,7 @@ def handle_events(self):
                     self.conn.start_next_cycle()
                     continue
                 self.cycle.more_body = False
-                self.message_event.set()
+                self.cycle.message_event.set()
 
     def handle_upgrade(self, event):
         upgrade_value = None
@@ -491,6 +491,7 @@ async def send(self, message):
             # Handle response completion
             if not more_body:
                 self.response_complete = True
+                self.message_event.set()
                 event = h11.EndOfMessage()
                 output = self.conn.send(event)
                 self.transport.write(output)
diff --git a/uvicorn/protocols/http/httptools_impl.py b/uvicorn/protocols/http/httptools_impl.py
index 15262326b..924e131ce 100644
--- a/uvicorn/protocols/http/httptools_impl.py
+++ b/uvicorn/protocols/http/httptools_impl.py
@@ -121,7 +121,6 @@ def __init__(self, config, server_state, _loop=None):
         self.headers = None
         self.expect_100_continue = False
         self.cycle = None
-        self.message_event = asyncio.Event()
 
     # Protocol interface
     def connection_made(self, transport):
@@ -146,7 +145,8 @@ def connection_lost(self, exc):
 
         if self.cycle and not self.cycle.response_complete:
             self.cycle.disconnected = True
-        self.message_event.set()
+        if self.cycle is not None:
+            self.cycle.message_event.set()
         if self.flow is not None:
             self.flow.resume_writing()
 
@@ -267,7 +267,7 @@ def on_headers_complete(self):
             access_logger=self.access_logger,
             access_log=self.access_log,
             default_headers=self.default_headers,
-            message_event=self.message_event,
+            message_event=asyncio.Event(),
             expect_100_continue=self.expect_100_continue,
             keep_alive=http_version != "1.0",
             on_response=self.on_response_complete,
@@ -288,13 +288,13 @@ def on_body(self, body: bytes):
         self.cycle.body += body
         if len(self.cycle.body) > HIGH_WATER_LIMIT:
             self.flow.pause_reading()
-        self.message_event.set()
+        self.cycle.message_event.set()
 
     def on_message_complete(self):
         if self.parser.should_upgrade() or self.cycle.response_complete:
             return
         self.cycle.more_body = False
-        self.message_event.set()
+        self.cycle.message_event.set()
 
     def on_response_complete(self):
         # Callback for pipelined HTTP requests to be started.
@@ -530,6 +530,7 @@ async def send(self, message):
                 if self.expected_content_length != 0:
                     raise RuntimeError("Response content shorter than Content-Length")
                 self.response_complete = True
+                self.message_event.set()
                 if not self.keep_alive:
                     self.transport.close()
                 self.on_response()